Such a coupling device is disclosed in the European patent application EP-A-0 794 378 assigned to the present applicant's assignee, to which U.S. application Ser. No. 08/790,146 corresponds, the entire disclosure of which is hereby incorporated by reference. The prior art coupling device is being used for pipes made of steel, stainless steel, eternite, cast-iron, coated steel, PVC, polyethylene and asbestos cement, and is intended for coupling two of such pipes. It is important that on the one hand the coupling device provides a sufficient seal, and that on the other hand the coupling device is able to withstand tensile strain. The latter function is provided by the grip ring which is part of the prior art coupling device.